1. Field of the Invention
The present invention relates generally to internal structures and mechanisms of an electronic connector of a cable. More particularly, the present invention relates to internal structures and mechanisms of an electronic controller of a cable used to electronically activate mission-critical safety devices in vehicles.
The present invention also relates to electric connectors for specific cables, namely, those that have a headshell deploying positive locking means to intermate the cable conductors to those in a receptacle on a device or in a receptacle on another cable assembly, with the locking means being substantially permanent or requiring a deliberate actuation of at least one mechanical component of the cable headshell mechanism in order to disengage the cable headshell from the receptacle.
2. Description of the Related Art
Electrical signals and electric power in vehicles are commonly transmitted by electrical cables grouped into a wiring harness. Wires within the harness are grouped into cables which are installed on electrical and electronic devices and modules throughout the vehicle. Electrical interconnection is afforded by cable end headshells containing a plurality of electrical contacts or terminals which intermate with complementary contacts and terminals in receptacles on the devices and modules.
More specifically, there exist connectors that provide for connection of signals and power transmitted through cable harness assemblies which attach to mission-critical safety devices. Since the receptacle is often fixed to structural components of the vehicle relative to the mating motion of the cable harness connector assembly, the connector headshell is considered to plug in to the receptacle and is often referred to as a plug-in connector.
Electrical connectors designed to plug in to mission-critical safety device units require exceptionally high levels of confidence in the efficacy and endurance of good electrical interconnect properties throughout the challenging physical environment of mechanical shocks, vibration, temperature variations, during the foreseeable service life of the vehicle. Additionally for these systems, it is critical to assure correct and reliable installation of the cable to its mating device during the initial assembly of the vehicle and during any repair or maintenance service in which a disconnect and a reconnect of a mission-critical safety device occurs.
Common approaches to assure correct and complete connection of a harness to a mission-critical unit include electrical continuity checks and visual inspection or verification that a cable end headshell is properly engaged with the mission-critical unit. Typical interconnect designs for these applications include snapping detents and physical locking and engaging features which prevent undesirable disconnection. Yet these design features are rarely fool-proof and invite an assembly error in which a partially or incompletely mated connector passes an assessment of its electrical interconnectivity while the physical locking features are not completely engaged and fully actuated.
The danger posed by a positive reading of electrical continuity plus a cursory visual inspection failing to detect that an installment is in fact incomplete is that subsequent vibration, shocks, and atmospheric oxidation in service can disconnect the cable or substantially degrade its electrical interconnect properties such that a mission-critical safety device fails to receive an electrically transmitted signal. One such example would be the explosive squibs used to deploy a passenger airbag failing to operate in a moment of dire need.
Of potential relevance to the invention, U.S. Pat. No. 7,238,039 entitled “Plug-in Connector Comprising a Secondary Locking Mechanism Impinged by a Spring Force” by Holweg, describes a plug-in connector, in particular for airbag retaining systems, that includes a first housing that can be locked in a mating connector by locking arms, and a secondary locking mechanism that can be loaded with a spring force. The secondary locking mechanism has tongues that block the locking arms after they are engaged in the mating connector, as well as detent arms, that are blocked by one edge of the mating connector during the introduction process, until the locking arms are engaged. At this stage, the detent arms are then adapted to slide off the edge wherein, as a result of the spring force that has been previously built up, the secondary locking mechanism is adapted to be moved into its final position.
Mating of the connector may be accomplished in a single motion, and moreover, the connector will provide a self-reject from an incomplete mating, albeit in an inefficient manner relative to the manner in a connector in accordance with the invention provides for a single motion connectivity to a receptacle with a self-reject facet.
Other connector connectivity assurance systems in the prior art of potential relevance generally include electromagnetic actuation or disengagement, rotating or pivoting components, keys, toggles, or rocker actuations, and other elements. Specifically, some latching and locking connectors have latching or locking beams or arms while also having some additional movable component that can reinforce the locked state of the connector by trapping the beam in its engaged state. These secondary or redundant safety features and methods of achieving such a safely redundant locked state are sometimes referred to in the industry as “connector position assurance,” and abbreviated as CPA. “CPA” as used in this specification is not to be confused with an abbreviation meaning “Continued Prosecution Application” as described in MPEP 201.06(d).
Besides CPA, the term “terminal position assurance” or “TPA” occurs commonly and describes the art of assuring that conductive terminals resist being pushed out the back end of a housing during a forward mating motion of a connector.
Examples of such connectors include the following:
Canadian Pat. No. CA2124127(A1) entitled “Electric Connector” by Hopf et al., describes a connector with locking beams that engage a standardized annular undercut in the receptacle during a mating motion of the headshell. A second motion is required to manually slide a locking component in a direction defined by the headshell, which second motion happens to be perpendicular to the mating axis defined by the approach of the connector to the receptacle.
Canadian Pat. Appin. No. CA2265177 entitled “Connector With Automatic Insertion and Ejection” by Boussairy et al., describes a device providing a mating action that is assisted or automated by a spring. There is no self-rejecting action during the mating of the device.
Canadian Pat. No. CA2277682(C) entitled “Connector Module” by Miller, et al., describes a connector module that includes a first connector housing, a second connector housing and a connector positive assurance member. Insertion of the first housing into the second housing causes a latching mechanism located within the assembled first and second housings to latch the housings together so that they cannot be readily disengaged. When the first and second housings are fully engaged in this manner, the connector positive assurance member may be moved from a first position to a second position to assure complete engagement has been effected and to lock the housings together. If the first and second housings are not fully engaged, the connector positive assurance member cannot be moved from such first position to such second position.
European Pat. No. EP0828268A2 entitled “Plug-in Snap Acting Mechanism” by Schaar, describes a mechanism that affords electrical disengagement if insufficient actuation force is applied and then released.
European Pat. No. EP1207591B1 entitled “Plug Connector with Secondary Locking Device” by Gunreben, describes a connector including spring arms that insert into an “arm pit” at the root of the locking arms from an opposite axial direction.
Japan Pat. Appl. No. 2000-159569 entitled “Electronic Device” by Mori, describes a pushbutton switch with a spring providing physical resistance to deter actuation, except by a deliberately sufficient force.
Japan Pat. Appl. No. 08-317870 entitled “Electric Switch” by Aulmann, assures a determinate actuation of the switch by forcing the user to operate a second extraneous element before interconnection by the primary means is achieved.
Japan Pat. Appl. No. 08-028549 entitled “Coupling Device For Switch With Operating Device” by Kozono, describes a headshell and engagement means including a drive shaft therein and oriented slits on the receptacle side, so that a primary coupling force is achieved by rotary mechanical advantage rather than a press-on motion.
Japan Pat. Appl. No. 06-196039 entitled “Separating Device Associated With Circuit Breaker” by Paggi, deploys pins (male features) on a headshell and pin-receiving terminals in a plug side.
Japan Pat. Appl. No. 2009-265042 entitled “Operation Switch” by Kawaguchi et al., describes an electric switch with leaf-spring contacts. There is no feature that confirms an efficacious and reliable locked interconnect condition to the user.
Japan Pat. Appl. No. 2005-156211 entitled “Push-Button Switch” by Tetsuya et al., provides for primary and secondary disconnect states, with the final preferred state maintained by the force of a stronger spring overriding that of a smaller, weaker spring.
Japan Pat. Appl. No. 2001-198540 entitled “Push-Lock Switch” by Seki, describes a headshell of a push-button housing that grips the outside of an assembly base, but not an annular recess in a separate receptacle. The movable internal component, called a pusher bar, must clear and subsequently lockingly engage a flange in the assembly base. Release from the locked state of this device is achieved by rotation of the button housing. Release from the locked state cannot be obtained by pulling the button housing away from the receptacle.
Japan Pat. Appl. No. 11-184285 entitled “Locking and Unlocking Mechanism of Cable Connector and Method for Locking and Unlocking” by Takahashi et al., describes a device having two unlocking assistance plates driven by a stirrup in a manual action by the user.
U.S. Pat. No. 5,183,410 entitled “Connector Assembly” by Inaba et al., describes a connector latching mechanism with a limited degree of self-rejection, and cantilever latch features that reside on the receptacle side of the design, and the trip mechanism for the internal sliding component is accomplished with a pivoting action of a rigid part.
U.S. Pat. No. 5,647,757(A) entitled “Electrical Connector With Terminal Position Assurance” by Chrysostomou, describes a connector with a headshell with a CPA member that operates an additional component called a support member by means of a camming motion. Thus, the second movement is distinct from the first mating motion. The connector therefore does not provide a more convenient single motion mechanism with automated triggering of the CPA, or self-rejection.
U.S. Pat. No. 5,746,618 entitled “Squib Connector for Automotive Air Bag Assembly” by Gauker, shows a device lacking a secondary locking action as well as lacking an automatic snap-on means therefor and self-rejecting action.
U.S. Pat. No. 5,848,912(A) entitled “Half-fitting Prevention Connector” by Okabe, describes a connector that includes a self-reject function, but incorporates its latching function into the sliding component. Latching is thus not a first and primary interaction between a housing and its complementary receptacle, with the slider following later so as to disable unlatching of these primary latching means.
U.S. Pat. No. 5,947,763 entitled “Bi-directionally Staged CPA” by Alaksin, describes a connector that requires a pivot motion for disengagement, and has a manually actuated secondary lock to prevent the pivotal motion. The connector does not offer automatic snap-in of the secondary lock and does not offer self-rejection.
U.S. Pat. No. 6,019,629(A) entitled “Connector” by Ito et al., describes a connector having a cantilever latch on a first headshell with a stub which, during mating, retards a spring-loaded slider component held in a complementary second headshell. A ramp of the slider has a predetermined angle such that a threshold of applied mating force, rather than a predetermined partial or complete mate position, trips the slider to move into a locking position. The slider does not have blocking features, but rather has a window to capture the stub on the aforementioned cantilever. This device will self-reject by means of the spring-loaded slider pushing itself off from the mating face of the complementary second headshell. However, no means of disconnection are disclosed, although pulling the pieces apart until something breaks is an obvious method usually directed to applications outside the scope of the invention such as where only a connection is authorized, and the breakage during disconnect is used to evince unauthorized tampering.
U.S. Pat. No. 6,024,595(A) entitled “Connector” by Saba et al., describes a connector that includes a slidable detecting member which is not spring-loaded, but rather is operated by a second motion after an initial mating motion. This device does not offer self-rejection from an incomplete mating attempt.
U.S. Pat. No. 6,325,663(B1) entitled “Half-fitting Prevention Connector” by Fukuda, describes a device with a self-rejection effect by means of a slider which includes a resilient portion integral to it. There is no discrete compression element such as a helical spring, nor a secondary locking or blocking function preventing unwanted disconnection in service.
U.S. Pat. No. 6,435,895(B1) entitled “Connector Position Assurance Device” by Fink et al., describes a complex slider component with its own latches, and assumes a complementary pair of connector headshells for mating immediately proximal yet extraneous to the connector housing. Upon a proper intermate of a pair of these generic connector housings, the component is moved further along the mating direction in a second movement so that its latches lock the headshells together while coming to rest, while ribs on a headshell block an unlatching motion.
There is no automatic spring-driven interlock or self-rejection action.
U.S. Pat. No. 6,468,104(B2) entitled “Connector” by Yoshihiro, describes a headshell of a first connector having a spring-loaded rotatable dowel with a radial stub which rotates the dowel while riding over the ramp face of a wedge located on a second mating connector. The mated pair is locked when the stored spring force rotates the stub behind the rear vertical face of the wedge. This device has no cantilever beam latches and no automatic locking or blocking beams able to prevent disconnect, and no effective mechanism for self-rejecting from an incomplete mating attempt.
U.S. Pat. No. 6,857,892(B2) entitled “Electrical Connector with Connector Position Assurance Member” by McLauchlan et al., describes two complementary connectors for intermating and includes a manually-driven CPA member requiring a second engaging motion separate from a mating motion of the connectors. The CPA component interferes with unlatching motion of a locked latch but this blocking feature of the CPA is a singular portion centrally located on the CPA.
U.S. Pat. No. 7,326,074(B1) entitled “Connector Position Assurance Device and a Connector Assembly Incorporating the Connector Position Assurance Device” by Lim et al., describes a connector that includes a cable headshell latchable to a complementary in-line cable connector housing by means of a larger primary latch. The headshell includes a movable component with its own pair of smaller secondary latches. The movable member is slid into latching engagement of its secondary latches to the connector housing and blocks the primary latch from unlatching. The secondary component requires a second movement by the user rather than an automatic stage and release action of an internal slider. Furthermore, the connector does not provide a mechanism for either visual indication of, or self-rejection from an incomplete mating.
U.S. Pat. No. 8,616,914 entitled “Checkable Plug-in Connection and Method for Checking the Connection State of a Plug-in Connection” by Mumper, describes a connector that includes a movable “verification element” on the headshell which becomes visibly displaced after a complete and locked mating attempt and this element functions as a tool to enable disconnection. The verification element can be removed by the installer to prevent unauthorized tampering with a confirmed correct mating condition, because the latching means can only be disabled by re-insertion of the verification element. There is no disclosure of providing for an automatic self-rejection from an incomplete mating.
U.S. Pat. Appin. Publ. No. 2002/0115338(A1) entitled “Connector and Method of Assembling a Connector” by Nakamura, describes a connector that offers self-rejection but does not include an automatically engaging secondary lock, or any blocking means in the secondary lock that are able to prevent disengagement of the primary lock.
U.S. Pat. Appin. Publ. No. 2009/0035980(A1) entitled “Connector and Connector Assembly” by Nakamura, describes a connector housing pierced with an inspection window and another component of a distinct color which indicates a complete mating attempt by moving into a visually verifiable zone in the window.
U.S. Pat. Appin. Publ. No. 2010/0233897(A1) entitled “Electrical Connector Assembly Having Connector Position Assurance Device” by Seo et al., describes a device having a manually actuated secondary lock, but does not offer automatic snap-in of the secondary lock or self-rejection.
U.S. Pat. Appin. Publ. No. 2011/0021060 entitled “Connector” by Urano et al., describes a connector with a manually actuated secondary lock. The connector does not offer automatic snap-in of the secondary lock or self-rejection.
U.S. Pat. Appin. Publ. No. 2004/0038569(A1) entitled “Connector and a Connector Assembly” by Yamaoka et al., describes a connector that provides for something similar to a spring-loaded self-rejection but, rather than including a tripping mechanism to release stored compressed force accumulated during the approach of the connectors being mated, the rejection force remains accumulated while a secondary redundant lock is established by an additional manual movement of a yet additional sliding component.
U.S. Pat. Appin. Publ. No. 2004/0192098 entitled “Electrical Connector With Spring/Back Self Rejection Feature” by Pavlovic et al., describes a connector that offers self-rejection from an incomplete mate, but does so by contacting the “abutment” surface of a receptacle directly with its resilient member. As the headshell continues in the mating direction, a rejection force is accumulated in the resilient member until, by means of a detent feature in this member, the rejection force is suddenly substantially reduced or redirected upon itself rather than against the receptacle. The connector does not provide a secondary locking of previously engaged latches.
U.S. Pat. Appin. Publ. No. 2006/0086900(A1) entitled “Connector” by Nakamura, describes a connector that includes components similar to the connectors of Lim et al. and Hopf et al. The connector assembly includes a cable headshell including a movable detecting member initially standing proud of the contour of the headshell, which detects an incomplete mating attempt by remaining blocked from allowing itself to be pushed down flush with the headshell contour until a complete mating attempt is made between the headshell and a complementary receiving receptacle. Similar to the Hopf et al. connector, an additional component slidably coupled to the headshell can slide over and cover the detecting member in a second motion perpendicular to and less convenient than the initial mating direction. Also like the Hopf et al. connector, the secondary component requires a second movement by the user, rather than an automatic stage and release action of an internal slider. Furthermore, the connector of Nakamura does not provide a mechanism for either visual indication of, or self-rejection from an incomplete mating attempt.
U.S. Pat. Appin. Publ. No. 2007/0254518(A1) entitled “Electrical Connector Having a CPA Plug” by Nealle, describes a connector that has a sliding CPA member substantially enclosed within a two-part connector housing, but lacks a spring or other compressive member to store and release compressive force to effect the automatic, snap-on locking action. Furthermore, the Nealle connector appears to employ flexural bending of both locking and blocking features. No helical spring, resilient member, or other driving mechanism is disclosed.
U.S. Pat. Appin. Publ. No. 2007/0264863(A1) entitled “Connector and a Connector Assembly” by Nakamura, describes a connector that includes latches on a slider and fins on latch cantilever beams, but does not include a spring-loaded slider and offers no self-rejection action.
U.S. Pat. Appin. Publ. No. 2014/0004732(A1) entitled “Connector Position Assurance Device for a Connector Assembly” by Heil et al., describes a connector that has a manually driven secondary lock operable by a second motion after a mating motion of two connector housings. This secondary lock is neither spring-loaded nor tripped at a predetermined point at which a confirmed complete mating attempt has been established.